Braided lines install - Need to borrow a torque wrench

[possum]

I have some braided lines coming from the US for my R6 next week and need a torque wrench to install them correctly. I've not installed lines before and don't want to guess the amount of force required. Once installed it'll be straight onto the track so really want to get the job done properly.

I've taken a look around and the cheapest wrench is $80, not really an amount I'm willing to pay for a once-off.

Is there anyone in the Canning Vale area / south of river that would be willing to lend me an adjustable wrench for a day or two? I'm an honest guy and will return it immediately.

[Rich...]

How do you do up all the other bolts on your bike?

[Crobbo]

Have you tired cashies?

[out_in_front]

Just tighten them up with a spanner, if the lines still leak, tighten them up some more?

[51 New West]

0408 007 430

[mcmurray]

Feel free to borrow mine.

[out_in_front]

FWIW - torque wrenches are typically between +/- 20-40% inaccurate for delivering the required amount of axial force through a bolt - which almost begs the question - why bother? Plenty of studies been done on the subject too, feel free to look it up on the web if you don't believe me.

[possum]

Rich - With a spanner/socket set? I apply what I believe is the appropriate force for the application, but with brake lines I would prefer to take a more educated approach.

out_in_front - thanks for the information. Even though they may be out by a fair margin, at least the measurement will somewhat support my 'feeling' when tightening the lines up.

Mcmurray and 51 New West, I'll be in touch when the lines arrive and borrow the wrench from whoever is most convenient? Thanks heaps.

Mcmurray, would you mind sending me a PM with a contact number?

[Manyak]

I have one in Thornlie you can borrow as well.

[Arwon]

FWIW - torque wrenches are typically between +/- 20-40% inaccurate for delivering the required amount of axial force through a bolt - which almost begs the question - why bother? Plenty of studies been done on the subject too, feel free to look it up on the web if you don't believe me.

what... have you got a source for this revelation, as i'm pretty sure mr Snap-on in my toolbox will be very interested.

also the one i made 30 yrs ago was very accurate

[Rich...]

They are accurate in the turning torque if calibrated correctly...

But as for that turning torque being converted into the correct tension on the bolt there are a lot of factors that affect it...

Damaged threads, lubed, unlubed are the most common...

But for the want of an ultra sonic bolt micrometer they are the best option we have, just use them correctly...

[out_in_front]

Yep what he said - here is SKF bearings take on it - http://www.skf.com/files/880426.pdf, pages 6 and 7 state anywhere from 20-60% accuracy rates when testing bolt tension. So even if your wrench is correctly calibrates, the axial load placed in the bolt can be significantly out. This is why tension to yield bolts were made - much more accurate, once the bolt starts to yield it holds that amount of axial force for a while. As long as you don't undo them they will keep holding that tension, usually they ask for a specific torque and then add an extra half turn.

[Loud]

I love the security of torquing bolts too, then I use a white paint pen to mark them.

Banjo bolts use a copper crush washer. So do bleed bolts on cooling systems. I don't torque bleed bolts of any type - the whole idea of a crush washer is to tighten it until it crushes (that's why their a one-use item).

Some hoses have a screw end which you can only get an open-ended spanner on to. You won't have much luck getting a torque wrench on to that... hand tight is the way to go.

I guess my point is that you can go to extreme lengths and start torquing hose clamps, but why? Unless it's an engine component relying upon a certain pressure to obtain a level of bearing crush I reckon "tight" is good enough (so long as you've enough mechanical experience to know what "tight" is).

Out of curiosity what torque setting does the manufacturer recommend?

[Arwon]

good info.

but basically if you lube the threads correctly and they are cut properly you can get to within 20% with a good torque wrench.

[possum]

Okay so by the sounds of it the torque wrench may not be required. I've just read the instructions and seen videos from reputable sources advising to use a torque wrench and apply 12 ft lb's of torque.

The lines I have purchased are banjo bolts using crush washers. When tightening crush washers, can you feel them crush?